Symptoms
After an incubation period of 3-6 days, symptoms include fever, chills, severe headache, nosebleeds, aching limbs, nausea, and fatigue. The infection may also be asymptomatic. In most patients, the disease is resolved within about a week. In a minority of about 15%, it takes a severe course after a short recovery period of up to one day. This manifests itself in a falling pulse, high fever, abdominal pain, liver damage, jaundice, bleeding, shock, convulsions and organ failure and can be fatal in up to 50% of cases. Recovery from the disease can result in chronic fatigue that lasts for several months.
Causes
The cause of the disease is infection with yellow fever virus, an RNA virus in the flavivirus family that is related to the TBE agent and West Nile virus. Yellow fever is currently found only in the tropical and subtropical regions of Africa and South America and, unlike other viral diseases, has not yet found its way to Asia. According to a WHO estimate, 200,000 people contract yellow fever each year. In many countries, few cases are reported, even among travelers returning home.
Transmission
The disease is transmitted by infected mosquitoes of the genus and . The virus circulates between wild primates, the mosquitoes and humans, or between humans and humans.
Diagnosis
Diagnosis is made by medical treatment based on patient history, clinical symptoms, and laboratory methods. Related diseases such as dengue, chikungunya, and malaria must be excluded.
Prevention
For drug prevention, a live attenuated vaccine has been available since the 1930s (Stamaril, 17D vaccine). The protective effect begins about 10 days after administration and is valid for 10 years. Vaccination is recommended for people living in or traveling to affected areas. In some countries, it is mandatory before entry. It can be administered at official vaccination centers. Appropriate addresses can be found on the website of the Federal Office of Public Health. It is important to avoid insect bites with various measures. Caution: -Mosquitoes bite in contrast to also during the day. Among the recommended measures are:
- Appropriate clothing
- Repellents, e.g. DEET, insecticides.
- Rules of conduct
Treatment
To date, no causal treatment with antiviral drugs exists. Treatment depends on the symptoms and must be hospitalized depending on the severity. Bed rest, adequate fluids, and analgesics are recommended. Non-steroidal anti-inflammatory drugs such as acetylsalicylic acid, which promote bleeding, should be avoided. Patients should be protected from insect bites to prevent further spread of the disease.